From October 11, 2021 the biochemistry laboratory is changing the way that LDL cholesterol (LDLC) is calculated on the lipid profile.
The current calculation (Friedewald’s formula) has been in use for almost 50 years. It estimates LDLC from the total cholesterol (TC), HDL cholesterol (HDLC) and triglyceride (TG) concentrations. The calculation assumes that triglyceride-containing lipoproteins contain a constant proportion of LDLC. This has been shown not to be the case and as the plasma concentration of TG rises, so does the proportion of cholesterol in the triglyceride-rich VLDL particles.